import { numFormat } from "../utils/util";

const analysis = {
  STDEVP: function(mean, array1d) {
    let cov = 0;
    for (let i = 0; i < array1d.length; i++) {
      let xi = array1d[i];
      cov += Math.pow(xi - mean, 2);
    }
    return numFormat(Math.sqrt(cov / array1d.length));
  },
  STDEV: function(mean, array1d) {
    let cov = 0;
    for (let i = 0; i < array1d.length; i++) {
      let xi = array1d[i];
      cov += Math.pow(xi - mean, 2);
    }
    return numFormat(Math.sqrt(cov / (array1d.length - 1)));
  },
  VARP: function(mean, array1d) {
    let cov = 0;
    for (let i = 0; i < array1d.length; i++) {
      let xi = array1d[i];
      cov += Math.pow(xi - mean, 2);
    }
    return numFormat(cov / array1d.length);
  },
  let: function(mean, array1d) {
    let cov = 0;
    for (let i = 0; i < array1d.length; i++) {
      let xi = array1d[i];
      cov += Math.pow(xi - mean, 2);
    }
    return numFormat(cov / (array1d.length - 1));
  },
};

export default analysis;
